We are investigating the biochemical changes which occur in noradrenergic neurons in the brain and sympathetic nervous system during acute and chronic exposure to environmental stress. We hope to discover how the functions subserved by noradrenergic neurons may be altered by these stress-induced chemical events. We are examining functions such as feeding behavior and blood pressure regulation which are mediated by noradrenergic neurons and which will, therefore, reflect disturbances in noradrenergic neurotransmission after stress exposure. Our experiments relate directly to the substrates of stress-induced disease in man. Our goals are to determine the contribution of noradrenergic neurons to stress-related behavioral and physiological disturbances and to identify mechanisms by which noradrenergic neuron function can be effectively maintained during stress.